Selectivity in measuring the thermodynamic temperature of an ionized gas with a noise thermometer based on a capacity transducer

1982 ◽  
Vol 25 (3) ◽  
pp. 240-241
Author(s):  
Yu. G. Korobchenko ◽  
Yu. S. Ivashchenko
Keyword(s):  
Thermodynamic Temperature ◽  
Ionized Gas ◽  
Noise Thermometer ◽  
Capacity Transducer

scholarly journals A SQUID-based primary noise thermometer for low-temperature metrology

2016 ◽  
Vol 374 (2064) ◽  
pp. 20150050 ◽  
Author(s):  
A. Kirste ◽  
J. Engert
Keyword(s):  
Low Temperature ◽  
Quantum Interference ◽  
International System ◽  
Thermodynamic Temperature ◽  
Uncertainty Budget ◽  
Standard Uncertainty ◽  
Primary Thermometry ◽  
Magnetic Field Fluctuation ◽  
Noise Thermometer ◽  
System Of Units

Practical temperature measurements in accordance with the international system of units require traceability to the international temperature scales currently in force. Along with the awaited redefinition of the unit of temperature, the kelvin, on the basis of the Boltzmann constant, in future its mise en pratique will allow the use of approved methods of primary thermometry for the realization and dissemination of the kelvin. To support this process, we have developed a DC superconducting quantum interference device-based noise thermometer especially designed for measurements of thermodynamic temperature in a broad temperature range from 5 K down to below 1 mK. In this paper, we describe in detail the primary magnetic field fluctuation thermometer and the underlying model applied for the temperature determination. Experimental measurement results are presented for a comparison with the Provisional Low Temperature Scale 2000 between 0.7 K and 16 mK including an uncertainty budget for the measured thermodynamic temperatures. In this set-up, the relative combined standard uncertainty is equal to 0.6%.

scholarly journals Primary current-sensing noise thermometry in the millikelvin regime

2016 ◽  
Vol 374 (2064) ◽  
pp. 20150054 ◽  
Author(s):  
A. Shibahara ◽  
O. Hahtela ◽  
J. Engert ◽  
H. van der Vliet ◽  
L. V. Levitin ◽  
...  
Keyword(s):  
Low Temperature ◽  
New Technologies ◽  
Thermodynamic Temperature ◽  
Uncertainty Budget ◽  
Noise Sources ◽  
Current Sensing ◽  
Noise Thermometer ◽  
Initial Comparison ◽  
User Friendly ◽  
Primary Current

The use of low-temperature platforms with base temperatures below 1 K is rapidly expanding, for fundamental science, sensitive instrumentation and new technologies of potentially significant commercial impact. Precise measurement of the thermodynamic temperature of these low-temperature platforms is crucial for their operation. In this paper, we describe a practical and user-friendly primary current-sensing noise thermometer (CSNT) for reliable and traceable thermometry and the dissemination of the new kelvin in this temperature regime. Design considerations of the thermometer are discussed, including the optimization of a thermometer for the temperature range to be measured, noise sources and thermalization. We show the procedure taken to make the thermometer primary and contributions to the uncertainty budget. With standard laboratory instrumentation, a relative uncertainty of 1.53% is obtainable. Initial comparison measurements between a primary CSNT and a superconducting reference device traceable to the PLTS-2000 (Provisional Low Temperature Scale of 2000) are presented between 66 and 208 mK, showing good agreement within the k =1 calculated uncertainty.

Temperature and its measurement

2017 ◽  
Author(s):  
Andrew Clarke
Keyword(s):  
Thermal Equilibrium ◽  
Isotope Fractionation ◽  
Thermodynamic Temperature ◽  
The Other ◽  
Deterministic Models ◽  
Triple Point Of Water ◽  
Temperature Scales ◽  
Classical Thermodynamics ◽  
The Relationship ◽  
Unit Of Temperature

Temperature is that property of a body which determines whether it gains or loses energy in a particular environment. In classical thermodynamics temperature is defined by the relationship between energy and entropy. Temperature can be defined only for a body that is in thermodynamic and thermal equilibrium; whilst organisms do not conform to these criteria, the errors in assuming that they do are generally small. The Celsius and Fahrenheit temperature scales are arbitrary because they require two fixed points, one to define the zero and the other to set the scale. The thermodynamic (absolute) scale of temperature has a natural zero (absolute zero) and is defined by the triple point of water. Its unit of temperature is the Kelvin. The Celsius scale is convenient for much ecological and physiological work, but where temperature is included in statistical or deterministic models, only thermodynamic temperature should be used. Past temperatures can only be reconstructed with the use of proxies, the most important of which are based on isotope fractionation.

The Structure and Morphology of the Ionized Gas in Starburst Galaxies: NGC 5253/5236

1999 ◽  
Vol 118 (2) ◽  
pp. 797-816 ◽  
Author(s):  
Daniela Calzetti ◽  
Christopher J. Conselice ◽  
John S. Gallagher III ◽  
Anne L. Kinney
Keyword(s):  
Starburst Galaxies ◽  
Ionized Gas ◽  
Structure And Morphology

Stellar and Ionized‐Gas Kinematics of the Seyfert 1 Galaxy NGC 3516

1997 ◽  
Vol 490 (1) ◽  
pp. 227-237 ◽  
Author(s):  
S. Arribas ◽  
E. Mediavilla ◽  
B. Garcia‐Lorenzo ◽  
C. del Burgo
Keyword(s):  
Ionized Gas ◽  
Gas Kinematics

scholarly journals Ionized gas kinematics of massive elliptical galaxies in CALIFA and in cosmological zoom-in simulations

2020 ◽  
Vol 635 ◽  
pp. A41
Author(s):  
Jan Florian ◽  
Bodo Ziegler ◽  
Michaela Hirschmann ◽  
Polychronis Papaderos ◽  
Ena Choi ◽  
...  
Keyword(s):  
Radial Profile ◽  
Major Axis ◽  
Velocity Fields ◽  
Host Galaxies ◽  
Ionized Gas ◽  
Massive Galaxies ◽  
Gas Kinematics ◽  
Major Merger ◽  
Ordered Motion ◽  
Integral Field

Context. Powerful active galactic nuclei (AGN) are supposed to play a key regulatory role on the evolution of their host galaxies by shaping the thermodynamic properties of their gas component. However, little is known as to the nature and the visibility timescale of the kinematical imprints of AGN-driven feedback. Gaining theoretical and observational insights into this subject is indispensable for a thorough understanding of the AGN-galaxy coevolution and could yield empirical diagnostics for the identification of galaxies that have experienced a major AGN episode in the past. Aims. We present an investigation of kinematical imprints of AGN feedback on the warm ionized gas medium (WIM) of massive early-type galaxies (ETGs). To this end, we take a two-fold approach that involves a comparative analysis of Hα velocity fields in 123 local ETGs from the CALIFA (Calar Alto Legacy Integral Field Area Survey) integral field spectroscopy survey with 20 simulated galaxies from high-resolution hydrodynamic cosmological SPHgal simulations. The latter were resimulated for two modeling setups, one with and another without AGN feedback. Methods. In order to quantify the effects of AGN feedback on gas kinematics, we measured three parameters that probe deviations from simple regular rotation by using the kinemetry package. These indicators trace the possible presence of distinct kinematic components in Fourier space (k3, 5/k1), variations in the radial profile of the kinematic major axis (σPA), and offsets between the stellar and gas velocity fields (Δϕ). These quantities were monitored in the simulations from a redshift 3 to 0.2 to assess the connection between black hole accretion history, stellar mass growth, and the kinematical perturbation of the WIM. Results. Observed local massive galaxies show a broad range of irregularities, indicating disturbed warm gas motions, which is irrespective of being classified via diagnostic lines as AGN or not. Simulations of massive galaxies with AGN feedback generally exhibit higher irregularity parameters than without AGN feedback, which is more consistent with observations. Besides AGN feedback, other processes like major merger events or infalling gas clouds can lead to elevated irregularity parameters, but they are typically of shorter duration. More specifically, k3, 5/k1 is most sensitive to AGN feedback, whereas Δϕ is most strongly affected by gas infall. Conclusions. We conclude that even if the general disturbance of the WIM velocity is not a unique indicator for AGN feedback, irregularity parameters that are high enough to be consistent with observations can only be reproduced in simulations with AGN feedback. Specifically, an elevated value for the deviation from simple ordered motion is a strong sign for previous events of AGN activity and feedback.

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